Cita APA

Azar, B. S., & Hagen, S. A. (2009). Understanding and using english grammar (4. ed.). New York: Pearson Longman.

Citación estilo Chicago

Azar, Betty Schrampfer, y Stacy A. Hagen. Understanding and Using English Grammar. 4. ed. New York: Pearson Longman, 2009.

Cita MLA

Azar, Betty Schrampfer, y Stacy A. Hagen. Understanding and Using English Grammar. 4. ed. New York: Pearson Longman, 2009.